A suspect in a fatal gas station shooting Tuesday night was high on PCP, Prince George's County police said.

Duane Lamar Williams, 34, was charged with first- and second-degree murder after authorities said he shot a man while the victim was pumping gas Tuesday night.

Police said they believe Williams was high on PCP when he approached the victim, Eric Eugene Walker, 27, of Baltimore, about 10:40 p.m. on the 2900 block of Colebrook Drive in Hillcrest Heights.

Williams showed a gun and chased Walker across Branch Avenue, where he shot him multiple times.

The passenger in the car was an off-duty D.C. police officer. He identified himself as an officer to make an arrest. Williams then pointed his gun and fired at the officer, but the gun failed to discharge.

Patrol officers found Williams nearby. Based on his erratic behavior, they believe he was high on PCP. Officers deployed their Tasers multiple times to try and subdue the gunman, but the electric shock did not seem to work on Williams, a common occurrence when someone is under the influence of PCP, police said.

Police eventually were able to arrest the gunman and recover the weapon, authorities said.